1997 CHEVROLET TAHOE Owners Manual

Downloaded from www.Manualslib.com manuals search engine If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
0 Tow a trailer. See “Driving on Grades” in the Index.
If you get the overheat warning with no sign of steam,
try this for a minute or
so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (a)
for automatic transmissions. If you
no longer have
the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign
of steam, push the accelerator until
the engine speed is about twice as fast as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes. Now see if the warning stops,
But then, if you still have the warning,
turn oflthe
engine
and get everyone out of the vehicle until it
cools down.
YOU may decide not
to lift the hood but to get service
help right away.
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Downloaded from www.Manualslib.com manuals search engine Cooling System -- Gasoline Engines
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan(s)
LA
CAUTION:
I
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start up even
when the engine is not running and can injure
you. Keep hands, clothing and tools away from
any underhood electric fan.
If the coolant inside the coolant recovery tank is boiling,
don’t do anything else until it cools
down.
5-13

Downloaded from www.Manualslib.com manuals search engine A CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you
do, you can be burned.
Don’t run the engine if there is
a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
The coolant level should be at or above the COLD mark. I NOTICE:
If it isn’t, you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere else in
the cooling system.
Engine damage from running your engine
without coolant isn’t covered by your warranty.
If there seems to be no leak, start the engine again. See
if the fan speed increases when idle speed is doubled by
pushing the accelerator pedal down.
If it doesn’t, your
vehicle needs service. Turn off the engine.
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Downloaded from www.Manualslib.com manuals search engine How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t at or above the COLD
mark, add a 50/50 mixture of
clean water (preferably distilled) and DEX-COOL@
(silicate-free) antifreeze at the coolant recovery tank. (See
“Engine Coolant” in the Index for more information.)
-
A CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will. Your vehicle’s coolant warning
system is set for the proper coolant mix.
CAUTION: (Continued) CAUTION:
(Conwed)
With plain water
or the wrong mix, your engine
could get too hot but you wouldn’t get the
overheat warning. Your engine could catch fire
and
you or others could be burned. Use a 50/50
mix of clean water and DEX-COOL@ coolant.
I NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mix.
5-15

Downloaded from www.Manualslib.com manuals search engine I A CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at or
above the
COLD mark, start your vehicle.
If the overheat warning continues, there’s one more
thing you can try. You can add the proper coolant
mix
directly to the radiator, but be sure the cooling system is
cool before you do it.
5-16

Downloaded from www.Manualslib.com manuals search engine A CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and
if you turn the radiator
pressure cap
-- even a little -- they can come out
at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap,
is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have to
turn the pressure cap.
I
5-17

Downloaded from www.Manualslib.com manuals search engine How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when the
cooling system, including the radiator pressure cap
and upper radiator hose, is no longer
hot. Turn
the pressure cap slowly counterclockwise until it
first stops. (Don’t press down while turning the
pressure cap.)
If you hear
a hiss, wait for that to stop. A hiss means
there
is still some pressure left.
2. Then keep turning the pressure cap, but now push
down as you turn
it. Remove the pressure cap.
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Downloaded from www.Manualslib.com manuals search engine 3. Fill the radiator with the proper DEX-COOL@
coolant mixture, up to the base of the filler neck.
4. Then fill the coolant recovery tank to the COLD mark.
5.
Put the cap back on the coolant recovery tank, but
leave the radiator pressure
cap off.
5-19